RATIONALE: Drugs used in chemotherapy, such as doxorubicin hydrochloride liposome and dexamethasone, work in different ways to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. Bortezomib may stop the growth of cancer cells by blocking some of the enzymes needed for cell growth and by blocking blood flow to the tumor. Giving bortezomib together with combination chemotherapy may kill more cancer cells.